This is the valve that was used to pressurise the shock with nitrogen when it was assembled. It's also the valve that can be used to release the nitrogen prior to safe disposal of the shock.

Whatever you do, don't be tempted to fiddle/tamper with the valve. It's under very high pressure (125+ psi normally) and the reservoir only contains a very small volume of gas, so the tiniest loss will have a massive impact on the pressure in the shock, in fact it will render it useless. The valve is only of any use if you have specialist equipment, it's not for the DIY mechanic!

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